Having a problem keeping the hard rubber mast wedges in place during sailing. Shrouds are perfectly tuned using a gauge. Back-stay off. I cannot tell at what point of sail the blocks fall out. My mast is set just touching the aft portion of the through deck partners. I am stumped on this. Any help would be appreciated.

I've been troubled by the same on a different type of boat. The cheap and easy solution I used was to use a big hose clamp (stainless of course) and a rag, just under the partners to hold the blocks up. Of course the rag needs to match your boats' colors....